The South China University of Technology

Wenliang Wang

Guoqiang Li

Deqi Kong

Sheng Chen

Yuan Li

Zhiheng Xing

Yuhui Yang

Zichen Zhang

Baiyu Su

Yulin Zheng

Zhengliang Lin

Wenjin Mai

Jixing Chai

Xiaochan Li

Linhao Li

Hongsheng Jiang

A preparation method for growing a germanium sulfide (GeS) single-crystal thin film on a SiOsubstrate includes: cleaning a surface of a substrate with acetone, ethanol and deionized water, where the substrate is a Si/SiOsubstrate or a SiOglass substrate; photoetching the substrate, spin-coating a photoresist, and performing photoetching and dry etching or wet etching to obtain a groove pattern; depositing a germanium (Ge)-crystal layer in the groove pattern of the substrate to obtain a treated substrate; and putting the treated substrate into a chemical vapor deposition (CVD) device for growth, a growth source being high-purity sulfur (S) powder and high-purity Ge powder, thereby obtaining a GeSsingle-crystal thin film on the SiOsubstrate. The preparation method can grow GeSsingle crystals on the SiOsubstrate. The GeSsingle crystals have a high crystalline quality and a small surface roughness.

Preparation method for growing germanium sulfide (GeS) single-crystal thin film on SiOsubstrate

The present invention discloses a solar-blind AlGaN ultraviolet (UV) photodetector and a preparation method thereof. The solar-blind AlGaN UV photodetector comprises an UV photodetector epitaxial wafer, including an undoped N-polar plane AlN buffer layer, a carbon-doped N-polar plane AlN layer, a carbon-doped N-polar plane composition-graded AlGaN layer, and an undoped N-polar plane AlGaN layer that are grown sequentially on a silicon substrate, and also comprises an insulating layer, an ohmic contact electrode, and a Schottky contact electrode arranged on the UV photodetector epitaxial wafer, as well as a SiNpassivation layer arranged on both sides of the UV photodetector epitaxial wafer, where x=0.5-0.8, y=0.75-0.95, and z=1.33-1.5. The present invention realizes the preparation of the high-performance solar-blind AlGaN UV photodetector, and improves the responsivity and detectivity of the AlGaN UV photodetector' in the UV solar-blind band.

Solar-blind AlGaN ultraviolet photodetector and preparation method thereof

An InGaN/GaN multiple quantum well blue light detector- includes: a Si substrate, an AlN/AlGaN/GaN buffer layer, a u-GaN/AlN/u-GaN/SiN/u-GaN buffer layer, an n-GaN buffer layer, an InGaN/GaN superlattice layer and an InGaN/GaN multiple quantum well layer in sequence from bottom to top. The multiple quantum well layer has a groove and a mesa, the mesa and the groove of the multiple quantum well layer are provided with a SiNpassivation layer. The passivation layer in the groove is provided with a first metal layer electrode with a semicircular cross section, and the passivation layer on the mesa is provided with second metal layer electrode.

InGaN/GaN multiple quantum well blue light detector combined with embedded electrode and passivation layer structure and preparation method and application thereof

The present invention provides a GaN/two-dimensional AlN heterojunction rectifier on a silicon substrate and a preparation method therefor and belongs to the field of rectifiers. The rectifier comprises a silicon substrate, a GaN buffer layer, a carbon-doped semi-insulating GaN layer, a two-dimensional AlN layer, a non-doped GaN layer, a non-doped InGaN layer and a SiNpassivation layer that are stacked in sequence. The rectifier further comprises a mesa isolation groove and a Schottky contact electrode that are arranged at one side. The mesa isolation groove is in contact with the non-doped GaN layer, the non-doped InGaN layer, the SiNpassivation layer and the Schottky contact electrode. The Schottky contact electrode is in contact with the mesa isolation groove and the non-doped GaN layer. The thickness of the two-dimensional AlN layer is only several atomic layers, thus the received stress and polarization intensity are greater than those of the AlGaN layer.

GaN/two-dimensional AlN heterojunction rectifier on silicon substrate and preparation method therefor

The present invention discloses a two-dimensional AlN material and its preparation method and application, wherein the preparation method comprises the following steps: (1) selecting a substrate and its crystal orientation; (2) cleaning the surface of the substrate; (3) transferring a graphene layer to the substrate layer; (4) annealing the substrate; (5) using the MOCVD process to introduce Hto open the graphene layer and passivate the surface of the substrate; and (6) using the MOCVD process to grow a two-dimensional AlN layer. The preparation method of the present invention has the advantages that the process is simple, time saving and efficient. Besides, the two-dimensional AlN material prepared by the present invention can be widely used in HEMT devices, deep ultraviolet detectors or deep ultraviolet LEDs, and other fields.

Two-dimensional AIN material and its preparation method and application

The present invention discloses a method for preparing a GaN rectifier suitable for operating at an alternating current frequency of 35 GHz: sequentially growing, on a silicon substrate, an N-polar GaN buffer layer, a carbon doped semi-insulated N-polar GaN layer, a non-doped N-polar AlGaN layer, a non-doped N-polar GaN layer and a non-doped N-polar InGaN thin film to obtain a rectifier epitaxial wafer; preparing a pattern groove for a schottky contact electrode on the GaN rectifier epitaxial wafer, and depositing the schottky contact electrode in the groove; preparing a pattern for an ohmic contact electrode, and depositing a device ohmic contact electrode on the surface of the epitaxial wafer; subsequently, depositing a silicon nitride passivation layer at a part where there is no electrode on the surface of the epitaxial wafer, and preparing a surface electrode area; and finally, performing mesa isolation treatment on the GaN rectifier epitaxial wafer. The present invention realizes the preparation of a high-frequency GaN rectifier, and improves the performance stability of a rectifier device operating at a high power.

Gan rectifier suitable for operating under 35GHZ alternating-current frequency, and preparation method therefor

The present invention discloses a vertical structure nonpolar LED chip on a lithium gallate substrate and a preparation method therefor. According to the method, LED epitaxial wafers are grown on a lithium gallate substrate, wherein the LED epitaxial wafers comprise a GaN buffer layer grown on the lithium gallate substrate, a non-doped GaN layer on the GaN buffer layer, an n-type doped GaN thin film on the non-doped GaN layer, an InGaN/GaN quantum well on the n-type doped GaN thin film and a p-type doped GaN thin film on the InGaN/GaN quantum well. Then, electrode patterns are prepared on the surfaces of the LED epitaxial wafers by the steps of spin coating, photoetching, developing and cleaning, and an electrode metal is sequentially deposited on the upper surfaces of the epitaxial wafers. Then, the LED epitaxial wafers are transferred to a copper substrate. Then, the original lithium gallate substrate is lifted off by an HCl solution, a silicon dioxide protective layer is prepared, and the corresponding part of an electrode is exposed. Then, SiOon the electrode is etched away, and a complete vertical structure LED chip is formed.

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Guangzhou, China

Wenliang Wang